2 years post-doctoral position (M/F)

CNRS - National Center for Scientific Research; France; Sur place; EUR 31 000 - 40 000; Plein temps

Résumé du poste

CNRS's Laboratoire Lorrain de Recherche en Informatique et ses Applications (LORIA) in Nancy invites applications for a two-year postdoctoral position focused on cryptography, designing and cryptanalyzing symmetric-key algorithms and secure encryption schemes.

The project emphasizes classical attacks such as linear and differential cryptanalysis, differential-linear and Boomerang techniques, and requires strong programming skills in C, Java or Python/SageMath, with team collaboration.

Qualifications

• PhD in Computer Science or Mathematics required.
• Strong knowledge in symmetric key cryptology and cryptanalytic methods.
• Proficient programming skills; C/Java/Python are pluses.

Responsabilités

• Design and develop new attacks on block ciphers, stream ciphers or hash functions.
• Study linear and differential cryptanalysis; analyze attacks using MILP, SAT or CP models.
• Collaborate with the CARAMBA team and implement models in tools like TAGADA or CLAASP.

Connaissances

Symmetric key cryptology

Programming in C

Programming in Java

Programming in Python/SageMath

Formation

PhD in Computer Science or Mathematics

Outils

TAGADA

CLAASP

Description du poste

Organisation/Company CNRS Department Laboratoire lorrain de recherche en informatique et ses applications Research Field Mathematics History History of science Researcher Profile First Stage Researcher (R1) Application Deadline 8 Oct 2026 - 23:59 (UTC) Country France Type of Contract Temporary Job Status Full-time Hours Per Week 35 Offer Starting Date 1 Nov 2026 Is the job funded through the EU Research Framework Programme? Not funded by a EU programme Is the Job related to staff position within a Research Infrastructure? No

Offer Description

This post-doctoral position research project lies in cryptography, which is the science developing algorithms to protect information and communications from malicious attackers. The objective is to focus on the design and cryptanalysis of symmetric key encryption algorithms and to propose various solutions for efficient and secure encryption.
In the domain of cryptography, a particular attention must be taken when looking at classical attacks against block ciphers such as linear or differential cryptanalysis. Those initial cryptanalyses have many possible extension and the aim of this post-doctoral position is to analyze some ciphers regarding those attacks. A particular attention will be taken when looking at differential-linear cryptanalysis and Boomerang attacks with the very recent results cited here. The differential-linear cryptanalysis is an old tool dating from 1994 but has been recently reconsidered with the introduction of a dedicated table and its finer analysis. The advances in the domain of Boomerang attacks follow many directions including probabilistiv extensions or dedicated computations of what is happening in the middle rounds. A particular attention would be to analyze, using those recent tools, the ARX schemes and particularly the latin dance schemes such as SALSA, ChaCha and so on.

The aim of this post-doctoral position research project is to build new attacks on block ciphers, stream ciphers or hash functions starting with studying linear and differential cryptanalysis. Then, a particular attention will be taken at differential-linear attacks or more generally at statistical or composite attacks. We will, after having fully understand the methods and the models (MILP, SAT or CP), develop models dedicated to other block ciphers or integrate the new models into a dedicated tool such as TAGADA, CLAASP or another tool.

This post-doctoral position is linked with the part of the CARAMBA team working on symmetric key crypt

The post-doctoral position thesis will take place over 2 years at the Lorrain Computer Science Laboratory (LORIA) in Nancy (France).analysis.

The applicant should have a PhD degree (or equivalent) in Computer Science or Mathematics and good knowledge in symmetric key cryptology. Good programming skills are required, and skills in C, Java or Python/SageMath are a plus. Good writing and communication skills are requested, together with the ability to work independently as well as in a team.